Hi psykoknarf,
There is no simple way of using bluetooth in the way which you describe. But you can use the access point function to connect in your car. This will work in the same way you describe for bluetooth.
- 1. Activate the access point function in the PI,
2. Connect to the Pi Access point with your smartphone (SYSID: RuneAudioAP, Password: RuneAudio - it will connect automatically if there is no other registered access point close by, SYSID and password can be changed),
3. Connect to the UI with '192.168.5.1' (this can also be changed).
Your existing WiFi configuration will still work for synchronising.
The Access Point functionality is available in these images:
for Pi 2/3B:
#44341 and:
#502522
for Pi B+/Zero/Zero W:
#371175
There is a possibility that it will not work 100% correctly if the Pi started when your synchronisation WiFi is in range. Let me know if this is a problem.
janui